1. Field of the Invention
This invention relates generally to stopper devices, and especially to a stopper designed so that it may be easily removed from the neck of a container with which it is used.
2. Description of the Prior Art
There are several problems with the design of the tapered stoppers which are in use today. One of these problems is due to temperature changes. When the temperature of the stopper and bottle is reduced, the difference in coefficient of expansion of the Teflon is much greater than that of the glass bottle. As the temperature is reduced, the difference in shrinkage between the Teflon and glass will allow the stopper to drop further into the taper of the bottle, and thereafter when the temperature is restored to normal room temperature, the stopper expands but cannot push itself up to its original position in relation to the taper. The expansion of the Teflon causes the stopper to be much tighter in the bottle neck than originally, and as a result it can become impossible to remove the stopper when the temperature difference is large. Furthermore, if the expansion of the Teflon is extreme, it can even break the glass container.
Another major cause of tight stoppers is due to the material in the bottle. When some of the material is removed from the container, the liquid must contact the tapered sealing portion of the bottle, and when the stopper is replaced, a film of liquid remains between the tapered surfaces. Depending upon the material in the container and the length of time between the next removal of the stopper, oxidation, evaporation, and other actions can cause the material to act as a glue, thus preventing the stopper from being removed.
A further problem with known-type stopper devices is that they are not normally designed for easy removal with a supplemental removal tool. By using such a supplemental tool with a specially designed stopper, the force needed to remove same from a container with which it is used can be substantially reduced.
Existing known prior patents which may be pertinent to this invention are as follows:
J. R. L. Martin, U.S. Pat. No. 2,526,622, 10/24/50 PA0 J. A. Clark, U.S. Pat. No. 3,842,790, 10/22/74 PA0 H. Dichter, U.S. Pat. No. 3,900,122, 8/19/75 PA0 J. Ruetz, U.S. Pat. No. 4,008,820, 2/22/77 PA0 R. J. Miskinis, U.S. Pat. No. 4,391,779, 7/5/83.
These patents generally show stoppers for sealing narrow neck bottles and containers in a secure manner.
U.S. Pat. No. 2,526,622 to Martin shows a bottle sealing stopper, especially in cross-section in FIG. 2, having a cone 13 which functions as a resilient spring to push outwardly upon the inner walls of the stopper body 10. Thus, the conical spring member 13 effectively urges body 10 radially outwardly in all directions so as to perform an extremely efficient sealing function. To remove the device, a fingernail or other object is inserted below the shoulder 11 and the stopper lifted upwardly.
The patent to Clark, U.S. Pat. No. 3,842,790, discloses another elastic closure member and also a tool for assisting in insertion and extraction of the closure member from the neck of a container. While the concept of this invention is similar to that of the present one, the specific structure for effecting same is substantially different therefrom.
The Dichter patent, U.S. Pat. No. 3,900,122, shows a stopper 11 having a resilient plug portion 12 which widens conically 14 towards the neck of the container and then tapers inwardly 15 therefrom. The cross-sections shown in FIGS. 1-3 best depict the features of this patent.
Ruetz U.S. Pat. No. 4,008,820 shows another stopper of plastic material having a gripping portion 1 and a substantially cylindrical sealing portion 2. The sealing portion 2 includes a cylindrical sealing wall 7 and a centering member 8 adjacent thereto, with the walls of the gripping portion, the centering member and the sealing wall all being laterally deformable. Again, the purpose of this patent is somewhat similar to that of the present invention, but the structure for effecting same is different.
The Miskinis patent, U.S. Pat. No. 4,391,779, shows a stopper 10 made with a Teflon body 12 with a retracting nut 22 threadably mounted on one end of the body for assisting in removing the stopper from a narrow neck container.
None of the above-listed patents teaches applicant's new and novel invention.